We went back and forth with WotC legal checking our monsters against MM2 monsters and cutting them from our product and Scott even checked for recent Dragon Mag conversions and cut those from our product. So we worked really hard to make sure that there was no overlap (other than Orcus and Skeleton Warrior and Demonic Knight, which I just HAD to rename and do). So I think you will see that there is no real overlap with MM2 or Book of Vile Darkness (unless WotC made a change that I dont know about). It was important to us that buyers not feel that they bought something from us and then had to buy the official version in a later product.
Clark